The Global Positioning System (GPS) and the associated receivers are widely used in survey applications. A high precision high accuracy survey system consists of one or more GPS receivers commonly called “rovers” plus an associated set of reference stations that produce additional measurements for use by the rovers. The method of position determination in which the rovers are supplied with and use these measurements in real time, to determine their position relative to a specified reference location is commonly known as the Real-Time-Kinematic method (RTK.) Alternatively, another popular method for high accuracy position determination collects the measurement data from the reference stations and from the rovers and performs a post-measurement process to provide an accurate position relative to the reference location.
A common concern in marketing and sales is the question of price structures. In order to address the different economic strengths of different countries and communities it is desirable to provide for different sales prices. This, however, creates the risk of grey market goods being imported into higher cost regions from low cost regions. The present invention seeks to address this concern.